So my engine decides to throw two CEL lights today. Running lean in bank 1 and 2. I have LT headers and CAI with a Steeda tune. Anyone know what is going on or what I'll have to do to fix it? It's my DD, so I'm screwed if something happens.

 

I propped the hood and wow it was really hot under there although the cylinder heads only got up to 207 degrees. Especially just for cruising around for a few minutes at low speeds (under 45)

My air to fuel ratio is 14-14.5 at idle and up to 15,16, and 17 with small revs. When driving, it stays around 14. When I brake, it goes all the way up and pegs out at 20.

 

Its because your cai. Did you get a tune for the air intake??

 

The custom Steeda tune was supposed I incorporate both the CAI and headers

 

I set the car back to stock, and then I retuned it. No CELs yet. Still wants to to go up to 20 in the fuel/air ratio. If I put a slight bit on the gas, it won't do it. It weird.

 

O2's still connected properly with the LT's? Aren't they relocated? Could the wire have come loose?

 

You know what? It could have. I went back to the shop yesterday to get my catback readjusted because it was hitting on the PH bar brace. It wasn't going off before then. I'll get up under the car and check.

 

Did the car run properly before you took it to the shop? If the car was running properly then popped the code ... then like you said ... you may have to check the connections.

If you are still throwing the code ... then shoot me an email at tim@steeda.com so that I can let Gus know he can see what is taking place.

Best Regards,

TJ

 

It wasn't until after. I didn't have any problems the few hundred miles I put on the car right after install

 

You really need a good custom dyno tune from a reputable tuner. You just can't trust a mail order tune especially with a daily driver. It's really worth the money for reassurance that you're not harming the engine. I'm sure the guys at Steeda know what they're doing but its just not same in my opinion.

 

I don't really like how the car shifts with the Steeda tune. It doesn't downshift well at all. It very firm and jerks forward a little bit. I'd like to dyno it anyways, so I'll look into that.

 

The a/f ratio pegging out on the high side under deceleration is normal

 

I am a big fan of Steeda. That being said if I was going to tune a 5.0 I would go to either VMP or AED.

 

I started getting running lean codes on my V-6. It ended up being a crack in my catch can hose and fitting. Just saying...........

 

Those are the same numbers that I have.. not sure about the revs.. never really noticed.
Sorry for the noob question... But what should the numbers be at idle, while just regular driving, and at WOT?
Stock car.
Thanks

 

I must add: My codes were bank 1 and bank 2 running lean. 99% of the time it is caused by a vaccum leak. Just saying...........

 

I look for leaks in the CAI hosing, but wasn't able to find any. I was hoping that's what it was because that's an easy fix.

 

Sometimes custom tune do not cover all add ons. I am a little surprised you put on after market headers. I may be wrong but I have been hearing the stock manifolds are better than any aftermarket on the current 5.0. But that is where your tune may be giving you issues. I hope you do find the problem and get it fixed. No fun to be burning up the engine on your ride. Goo luck.

 

to clarify my statement this is Based on the v8 and may not be true on the v6.

 

The stock headers looked like cheap crap when I took them off. Plus, they don't give you the sound that LT headers will.